Different sensory test for evaluation of freshly made food stuffs

1. Ningappa Kirasur
Dept. of Olericulture
2014-12-129
Acceptance-preference test

2. • Appearance of a food is the most important rather vital aspect
of sensory evaluation
• It is based on the visual appearance and palatability of the
product
• Their main objective is to determine the consumers’
acceptance of certain food products
• Acceptance and preference tests are widely used at the
development and launching stages of new products
Introduction

3. A .Difference test B. Rating test/
preference test
C.Sensitivity test Descriptive test
A1. Paired comparison test
B2. Duo- Trio test
A3. Triangle test
B1. Ranking test
B2. Single sample (monadic) test
B3. Two-sample difference test
B4.Multiple sample difference
test
B5. Hedonic rating test.
B6. Numerical scoring test
B7. Composite scoring test
C1. Sensitivity threshold
test
C2. Dilution test

4. 1. Ranking test
 Used to determine how several samples differ on the basis of
a single characteristic
 Panelist are presented all samples with code number and are
asked to rank
 The Panellist are asked to rank the coded samples according
to there preference

5. Ranking test
Name…………………
Date……………..
Product………………….
• Please rank the samples in numerical order according to your
preference or intensity of aroma/taste characteristic of the
product.
Intensity/preference sample code
1 ______
2 ______
3 ______
4 ______
Signature

6. • The panellist is asked to indicate the presence or absence and
intensity of a particular quality characteristic
• Analysis of two or more samples evaluated at different times
• By a different set of untrained panellists can be compared
2. Single sample test

7. Single sample test
Name………………… Date……………..
Product………………….
• Please taste and rank the samples carefully. can you detect
any off-flavour in the product? Circle one
Yes NO
If you detect any off-flavour Please it below.
Intensity comments
Trace off-flavour is due to-
Moderate off-odour
Strong off-taste
residual taste
other defects
Signature

8. 3. Two sample difference test
 This test is variation of the paired test and measure the amount of
difference
 Each taster is served four pairs of samples
 In two pairs duplicate samples. other two pairs test samples
 To judge the independently difference between the test sample a
standard on a scale ‘0’ representing no difference to ‘3’
representing extreme difference
 The panellist is not guess and he is guessing through the coded
duplicate standard in two pairs

9. Two sample difference test
Name………………… Date……………..
Product………………….
1.Compare the coded samples in each of the four pair given, test may or may not be
different from the reference sample.
2.Determine the degree and direction scale
Degree Direction
No difference 0 Super to standard S
Very slight difference 1 Equal to standard E
Moderate difference 2 Inferior to standard I
Large difference 3
3.Comment on what the difference is based on;taste,odour or both.
sample Degree Direction Comment
code no, difference
_______ _______ _______ ________
_______ _______ _______ ________
_______ _______ _______ ________
_______ _______ _______ ________
Signature

10. 4. Multiple sample difference test
• Each panellist is served 3-6 samples
• One sample is a known standard, panellist compares each
coded sample with the known standard
• One coded sample is a duplicate of the sample
• The panellist is not to guess. Direction and degree of
difference is also to be judged

11. Multiple sample difference test
Name………………… Date……………..
Product………………….
 Taste it carefully for the quality characters to be evaluated to the reference sample for odour
and flavour.
 Rate in each sample degree of difference and the direction of quality.
Degree of difference Direction of quality
Rating Difference from standard
0 None E Equal
1 slight I Inferior
2 moderate S Superior
3 large
sample code no odour flavour
Degree Direction comments Degree Direction comments
Signature

12.  One of the method for studying the consumers’ acceptance of
a certain product is to determine how much they like it when
they are consuming
 In 1940 the hedonic scale was developed at Quartermaster
Food and Container Institute of the US Armed Forces
 In order to predict the acceptance of certain canteen food
products by soldiers
5. Hedonic Rating Test

13.  Prepare the food samples
 Ask each taster to taste each sample in turn and tick a
box, from '1 Dislike Very Much' to '5. Like Very Much‘ to
indicate their preference
 This is a 5-point-scale Sometime a 9-point-scale is used
 The taster may also wish to make remarks about the
products’ appearance, taste, odour and texture
 Analyze the results. Which sample received the highest/lowest
scores? Which sample was preferred
Contd…

14. Name:………………… Date:……………..
Product:………………….
• Taste these samples and checking how much you like or dislike each one
• Use the appropriate scale to show your attitude by checking at the point
that best describe your feelings about the sample.
code code code
Like extremely ____ ____ ____
like very much ____ ____ ____
like moderately ____ ____ ____
like slightly ____ ____ ____
like or dislike ____ ____ ____
Dislike slightly ____ ____ ____
Dislike very much ____ ____ ____
Dislike moderately ____ ____ ____
Dislike extremely ____ ____ ____
Reason
Signature
Hedonic Rating Test

15. 6. Numerical Scoring test
• One or more samples are represented to each panelist
• Panelist evaluates each samples on a specific scale for a
particular characteristics indicating the rating of sample
• The panellists are trained to follow the sensory characteristics
corresponding to the agreed quality descriptions and scores

16. Numerical Scoring test
Name…………………
Date……………..
Product………………….
Please rate these samples according to the following descriptions
Sample Score Comment
Sample score comments
Signature

17. 7. Composite Scoring Test
• The rating scale is defined, so that specific characteristic of a
product are rated separately
• This method is helpful in grading products and comparison of
quality attributes by indicating which characteristic is fault in
a poor product
• It gives more information than the straight numerical method

18. Composite Scoring test
Name: …………………. Date:…………..
Product: Orange Marmalade
Quality Possible score Sample scores
Colour 20 ___ ___ ___ ___
Consistency 20 ___ ___ ___ ___
Flavour 40 ___ ___ ___ ___
Absence of defects 20 ___ ___ ___ ___
Comments
Signature

19. Number of Panel members and samples required for
sensory test
1. Ranking Trained
Semi-Trained
Un-Trained
5-12
10-15
72-80
2-7
2. Single sample Trained
Un-Trained
6-25
72-80
1
3. Two sample difference Trained 6-25 4 pairs of Unknown and control
sample
4. Hedonic Semi-Trained 10-25 5-10
5. Numerical scoring Un- Trained
Trained
72-80
5-12
1-4
1-6
6. Composite Trained 5-12 1-4
7. Multiple sample Trained
Semi-Trained
6-25
10-15
3-6
Sl.No Method Panellists No. of sample tests

20. Conclusions
 Even though affective studies are one of the most important
areas in the sensory evaluation field
 Acceptance as well as preference tests present some challenges
that have led by researchers
 These tests are not as simple as they may seem and results
should be carefully interpreted

21. Contd…….
• There are still several issues to be studied that are generating
future research studies in the area
• Alternative techniques are being developed to determine the
acceptance of certain products by consumers
• But their applicability still has to be analyzed and results
compared with the ones obtained using traditional tests